【单选题】The physiological significance of delay in AV node is
A.
making the ventricular muscles not to produce the complete tetanus
B.
enhancing the contractility of cardiac muscles
C.
lengthening the effective refractory period of the ventricular muscles
D.
permitting completion of atrial systole before the ventricular systole
E.
increasing the amplitude of the action potential in the cardiac muscles
【简答题】信用证(二) Issue of Documentary credit FROM : CITI BANK, TORONTO TO : BANK OF CHINA JIANGSU BRANCH 40A: FORM OF L/C: IRREVOCABLE 20: L/C NO . : 001/ 02 /14020X 31C: ISSUE DATE 1 6 . 0 4 .2 8 31D: EXPIRY D...
【判断题】绿色供应链管理的核心是使用最少的资源以及在不造成环境破坏及污染的情况下,生产及使用,回收该产品。()
【单选题】Which of the following is True about the heart?____
A.
The blood is pumped into the right ventricle and to the pulmonary artery to be sent to the lungs where carbon dioxide is removed and oxygen is added.
B.
During the systole, oxygenated is pumped out of the right ventricle into the aorta and from there through the veins to all organs of the body.
C.
There are four chambers which are made up of several layers of smooth muscles.
D.
The heart is roughly the size of the your fist.
【判断题】绿色供应链管理的核心是使用最少的资源以及在不造成环境破坏及污染的情况下,生产及使用,回收该产品。
【单选题】When the heart rate is too fast, the most obvious shortening is: ()